For example, in a patent document, Japanese Patent Laid-Open No. 2010-509825 (patent document 1), an idea of frame transfer between the nodes via a shortest path in an Ethernet network is disclosed (Ethernet: registered trademark). The shortest path is a shortest communication path in which the number of repeaters through which the frames pass to reach a destination node (i.e., a relay number, or “HOPS”) takes the minimum value.
In the repeater that adopts the idea of the patent document 1, when frames with the same address are received simultaneously from two or more ports, each of the received frames will be transmitted to the shortest communication path among two or more communication paths which lead to the node of the destination address. In such case, each of those frames are concentrated into one communication path.
Therefore, for example, when each frame is a large amount data frame, such as the one including a camera image data, it is highly possibly the case that the communication speed will be restricted to the maximum communication speed of the one of the plural communication paths. Further if such a restriction arises, each of the same address frames simultaneously received from two or more ports, i.e., the frames simultaneously transmitted from many nodes to the same address cannot be efficiently transmitted to the node of the destination address.